both about the same
they both work at about the same efficiency. You're right on with your thinking, aside from the fact that the Bmk-11 has a resistor installed in the return line. I think this is done because they don't want to divert TOO much oil away from the full flow system which protects your engine, but i'm not totally sure on that.
Just a note- many tap the return line into the valve cover instead of the sump, this may be easier for you, I dunno.
2004 Ram 2500 Cummins HO
2000 Jetta TDI
1999 E300 (sold)